A movie showing the
heating and eventual melting of a nail, and the
theoretical blackbody curve produced in the process.
Note: radiant heating and cooling systems operate
between 60°F and 90°F
surface temperatures which corresponds approximately to
far infrared wavelengths of 9.5 μm to 10 μm
respectively. This range is not even close to the 6000 K
(10,340°F) solar
temperature measured just below the photosphere, i.e.
daylight at shortwave lengths of 0.5 μm;
this is important to consider when people incorrectly
state that floor heating heats you like the sun....if
this were true your house would be on fire. This simulation is part of the Light & Spectra module of
the ClassAction project, a collection of
think-pair-share questions and resources for astronomy
education.

Source Credit: The NAAP
Basic Coordinates and Seasons Lab, used with permission.

Calculating wavelength from a surface
temperature

Wien's Displacement law

ʎ ∙
T= 2.898 mm·K ∙
1000, T
in K, ʎ
in μm

Solar

Floor Heating

Floor Cooling

Constant, mm· K

2.898

Surface temperature in Kelvin,
T

6000

305

292

Wavelength in microns, ʎ

0.48

9.50

9.92

Units:

Micrometer (μm),
a micrometre is an SI unit of length equal to
1,000,000 of a metre. It is also commonly known as a
micron. It can be written as 1 m / 1,000,000.

Nanometer (nm), a
nanometre is a unit of length in the metric system,
equal to one thousand-millionth of a metre, which is
the current SI base unit of length. It can be
written as 1 m / 1,000,000,000.